Various chemical and biological agents are used on commercially grown fruit to control the timing of fruit ripening. Such agents can be used for a variety of purposes. One purpose is to synchronize the ripening of fruit to assist in efficient harvesting of fruit from the field. Another purpose is to prevent drop off of fruit so that fruit remain on the plant or tree until the appropriate ripening time period. Another purpose of fruit ripening agents is to enhance color development in the fruit so that the fruit has a better and more uniform color as expected by retail consumers of the fruit. In the United States, it is current practice for many types of fruit to be treated with one or more such agents during the cultivation process.
Some agents previously used for control of fruit ripening are purely synthetic agents found to have desired effects on the fruit in question. Unfortunately, both due to issues of potential toxicity or oncogenicity, several such synthetic chemical fruit ripening agents have either been banned or had their use sharply curtailed due to commercial or consumer resistance to the products. One well known example of this phenomenon is the chemical Daminozide, sold under the tradename Alar, which was used as a fruit ripening agent on apples until banned in the United States following public controversy regarding potential oncogenicity reported in animal tests. Accordingly, there is a need for such fruit ripening control agents which are not synthetic chemicals in origin but which are biologically derived materials which are much less likely to have any undiscovered carcinogenic effect and which are much more likely to be readily accepted by the commercial interests and the consuming public.
Phosphatidylethanolamine is a fatty acid normally found in lipid layers in biological tissues. It is a phospholipid with two fatty acid groups. It is found abundantly in egg yolk. By the removal of a single fatty acid from phosphatidylethanolamine, lysophosphatidylethanolamine, often referred to below as "LPE," is created. LPE is commercially available from Sigma-Aldrich. LPE is present naturally in small quantities in plant tissues and other biological materials. The quantity of LPE present is increased significantly when natural lipid degradation occurs such as in aging plant tissues.